Update on my X5. Took the vehicle to the shop and they took the motor apart. The chain snapped in two places on the driver side. The plastic timing chain guides crumbled in pieces. They removed the heads and 4 out of the 8 cylinders were shot. I then bought a motor for $3000 + $1400 labour, $280 for new water pump, belts + 250.00 for shop supplies & fluids + $130 for oil pan heater. Over $5000.00 what a costly one. My worries is that it will happen again. What other regular maintnance should I do to prevent this from happening? I was told that its common for those plastic guide rails crumbles apart and you will never know cause its all internal. The best way to see is to drop the oil pan to see if theres any plastic pieces in there.

Wow... $5000 worth of repairs.

The Truck has a wholesale value of $4800 with around 180K on it.
You might have been better off buying something else and stripping this thing for parts.

Sorry you had to go through this, just after you bought it.

Was the engine rebuilt or used for $3000?
You might want to consider driving it for the summer and selling it near winter time.

Timing chains in general usually out live the vehicle.
There are a few exceptions.... I didn't know the X5 was one of them...